1. Field of the Invention
The present invention relates to a method of manufacturing a thin film transistor (“TFT”) substrate. More particularly, the present invention relates to a method of manufacturing a TFT substrate capable of simplifying manufacturing processes thereof.
2. Description of the Related Art
In general, a liquid crystal display (“LCD”) apparatus includes a TFT substrate, a color filter substrate and a liquid crystal layer. The TFT substrate includes TFTs and pixel electrodes. The color filter substrate includes color filters and a common electrode. The liquid crystal layer is disposed between the thin TFT substrate and the color filter substrate.
A process of manufacturing a TFT substrate is carried out through a photolithography process using a mask. Recently, a four mask sheet process using only four masks has been developed for simplifying the manufacturing process.
For etching a data metal layer using the four mask sheet process, a first etching stage for forming data lines and a second etching stage for etching a channel region are carried out.
Since a wet etching process is applied to the first and second etching stages in a conventional four mask sheet process, a width of a line becomes larger for reducing an increase of a width of a channel and a dispersion of a process.
In order to solve the above-mentioned problem, a manufacturing process using a wet etching process for the first etching stage and a dry etching process for the second etching stage has been developed. However, using both the dry etching process and wet etching process in the manufacturing process is complicated, and increases manufacturing time.